Annoyance with respect to odour is a set of complex reactions that takes place when repeated or continued exposure to that odour takes place. Ultimately, annoyance may lead to a complaint. Note that the absence of complaints does not necessarily indicate the absence of an odour problem.
The annoyance process can be summarized by an odour emission that leads to an exposure at a receptor (person). The receptor perceives the odour and judges it as unwanted, potentially creating an annoyance sufficient to lead to a complaint.